Lifting-jack



` UNITED STATES PATENT OFFICE.

GEORGE BENJAMIN, OF AVOCA, NEW YORK.

LIF'IIN G-J ACK.

Specification of Letters Patent No. 30,043, dated September 18, 1860.

To all whom it may concern:

Be it known that I, GEORGE BENJAMIN, of Avoca, in the county of Steuben and State of New York, have invented a new and Improved Lifting-J ack; and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawing, making a part 0f this specification, in which the figure is a perspective view of the whole.

A, is the base or platform, of any convenient size or strength to suit the purpose to which the jack may be applied; there is a hole in the center or between t-he posts for passing a chain or rope through when the jack is t0 be used for raising weights that are below it.

B and B, are uprights or posts with their lower ends secured into the base A. They must be placed so far apart as to allow the lever to pass freely between them. The tops of these posts-are secured together by a cap that may have a hole in its center to hold one end of the lever when the jack is not in use; the insides of these posts are fiattened to receive and hold the plates C, C.

C and C, are fulcrate plates. They may be made any dimension required. They are both made alike and are secured to the inner sides of the posts B, B by bolts or screws; they are provided with fulcrums at each edge placed alternately. These fulcrums are made so that when the lever is moved up or down the bearings of the clasps E and F will incline to the center of the plates and when necessary they will hold the bearings of both clasps at the same time, thus securely holding the lever in any required position. or if the jack was to be used with the 'upper end down the bearings would work the same in the plates; so that when necessary the jack may be secured overhead and the lever turned over so that the chain may pass through the cap on the ends of the uprights and thus lift weights that are below the ]ack.

D, is the lever, it may be made of wood or iron, it is provided with a hook or eye at the lower edge to attach a chain to, when the jack is used to lift weights that are far below it. The lever may have a handle at each end if necessary. It is also provided with clasps E and F and staples for the handles of the clasps to pass through.

E and F are clasps that extend around the lever they are provided each with a bearing at the under side that extends outward into the fulcrums of the plates C and C these clasps must be made so as to pass between the plates C and C, and each clasp is provided with a handle.

G and H are handles to the clasps E and F. They may be made any length required so as to be convenient to the operator; one of these handles should be on the upper and the other on the lower edge of the lever so that the operator may be enabled to actuate the jack without assistance.

I, is a chain that is hooked to the underside of the lever. It is used to attach the jack to any weight that it may be required to raise.

What I claim as new and desire to secure by Letters Patentis- The combination and arrangement of a lifting apparatus consisting of uprights B and B, fulcrate plates C and O and clasps E and F provided with latches G and H substantially as and for the purpose described.

GEORGE BENJAMIN.

Vitnesses CHARLES KETCHUM, MYRON BENJAMIN. 

